You can get PS2 games running on non-backwards compatible PS3s by downgrading them to 2.60 or lower then doing a trick.
The thing is though, in order for PS3s to downgrade to an older firmware they need to have been on that firmware already at some point.
and newer models come with newer firmware versions pre-installed all the time, so slims won't work for that reason.

The trick uses a work-in-progress official PS2 emulator someone found hidden in the firmware version, the emulator is gone on the 2.70 firmware and onwards.

You can get PS2 games running on non-backwards compatible PS3s by downgrading them to 2.60 or lower then doing a trick.
The thing is though, in order for PS3s to downgrade to an older firmware they need to have been on that firmware already at some point.
and newer models come with newer firmware versions pre-installed all the time, so slims won't work for that reason.

The trick uses a work-in-progress official PS2 emulator someone found hidden in the firmware version, the emulator is gone on the 2.70 firmware and onwards.

The Cobra-USB Dongle can re-enables the old PS2 Emulator in 3.41 Consoles (Slim or Phat)
But it is buggy , Slow and the compatability sucks.

It is much better to find an original Backwards compatible PS3 and use the Cobra-USB dongle to enable PS2 ISO loading.

I know this is 5 years later but i was hoping i could get help, so i have a psp 1001 and i just got it for cheep its running 3.52M33 V4 and i was hoping i could somehow get it to 1.50 ofw that way i...